Pin to reduce relative rotational movement of disk and spacer of turbine engine

ABSTRACT

An axial compressor of a turbine engine includes a plurality of disk and spacer pairs oriented along a common axis of rotation. Each of a disk and a spacer of the disk and spacer pairs has a contacting face defining an engagement between the disk and the spacer. The contacting face of each of the disk and the spacer includes a recessed area. A pin has a stem received within the recessed area of the disk and a head received within the recessed area of the spacer. The head of the pin includes at least two flats corresponding to complementary surfaces of the recessed area of the spacer.

TECHNICAL FIELD

The present disclosure relates generally to turbine engines and, more particularly, to a pin for reducing relative rotational movement of a disk and a spacer of an axial compressor of the turbine engine.

BACKGROUND

Some axial compressors of turbine engines use spacers to provide an inner flowpath for working fluid. The spacers are typically thin rings, installed onto each of a plurality of disks of the axial compressor. An interference engagement or, more particularly, a thermal interference engagement and a small cylindrical anti-rotation pin are used to couple each spacer to a corresponding disk. The disk and spacer pairs are oriented along a common rotational axis of the axial compressor. During a hot shutdown of the turbine engine, the spacers typically cool and shrink at a higher rate than the corresponding disks, thereby relieving the thermal interference engagement. The rotational inertia of the spacers often breaks the pins, allowing the spacers to rotationally shift relative to the corresponding disks from the factory set positions. To reset the imbalance, the turbine engine may require removal from service and disassembly.

U.S. Pat. No. 8,840,375 to Virkler discloses a lock assembly for a gas turbine engine. The lock assembly includes a lock body with an undercut slot that receives a retaining wire of a polygon shape. A rotor disk has a circumferentially intermittent slot structure extending radially outward relative to an axis of rotation. A component defined about the axis of rotation has multiple radial tabs extending radially inward relative to the axis of rotation. The radial tabs are engageable with the intermittent slot structure. A lock assembly, which includes the retaining wire, is engaged with at least one opening formed by the intermittent slot structure to provide an anti-rotation interface for the component.

As should be appreciated, there is a continuing need to improve efficiency and reliability of turbine engines and components of turbine engines.

SUMMARY OF THE INVENTION

In one aspect, an axial compressor of a turbine engine includes a plurality of disk and spacer pairs oriented along a common axis of rotation. Each of a disk of the disk and spacer pairs and a spacer of the disk and spacer pairs have a contacting face defining an engagement between the disk and the spacer. The contacting face of each of the disk and the spacer includes a recessed area. A pin has a stem received within the recessed area of the disk and a head received within the recessed area of the spacer. The head of the pin includes at least two flats corresponding to complementary surfaces of the recessed area of the spacer.

In another aspect, a method of operating a turbine engine includes steps of rotating a disk and spacer pair of a plurality of disk and spacer pairs about a common axis of rotation, and engaging a contacting face of a disk of the disk and spacer pair with a contacting face of a spacer of the disk and spacer pair during rotation. The method also includes a step of restricting relative rotation of the disk and the spacer using a pin having a stem received within a recessed area of the disk and a head received within a recessed area of the spacer. The restricting step includes contacting at least two flats of the head of the pin with complementary surfaces of the recessed area of the spacer.

In yet another aspect, a turbine engine includes an axial compressor. The axial compressor includes a plurality of disk and spacer pairs oriented along a common axis of rotation, with each of a disk of the disk and spacer pairs and a spacer of the disk and spacer pairs having a contacting face defining an engagement between the disk and the spacer. The contacting face of each of the disk and the spacer includes a recessed area. A pin has a stem received within the recessed area of the disk and a hexagonally shaped head received within the recessed area of the spacer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial cross section of an axial compressor of a turbine engine, according to an exemplary embodiment of the present disclosure;

FIG. 2 is a perspective view of an exemplary pin that may be used with the axial compressor of FIG. 1, according to the present disclosure;

FIG. 3 is a first side view of the exemplary pin of FIG. 2;

FIG. 4 is a second side view of the exemplary pin of FIG. 2;

FIG. 5 is a top view of the exemplary pin of FIG. 2;

FIG. 6 is a partial cross section of the exemplary pin of the previous FIGS., assembled with a disk and a spacer of a turbine engine;

FIG. 7 is a section view taken along lines 7-7 of FIG. 6;

FIG. 8 is a perspective view of the spacer of the present disclosure;

FIG. 9 is an enlargement of a portion of the spacer of FIG. 8;

FIG. 10 is a section view taken along lines 10-10 of FIG. 9; and

FIG. 11 is a flow diagram of an exemplary method of operating a turbine engine, according to the present disclosure.

DETAILED DESCRIPTION

A portion of an exemplary turbine engine 10 is shown generally in FIG. 1. In particular, a section view of an axial compressor 12 of the turbine engine 10 is shown. As will be appreciated by those skilled in the art, the turbine engine 10 may also include a combustor and a power turbine and/or a variety of additional or alternative components for compressing gas. The axial compressor 12 may include a plurality of disk and spacer pairs 14 oriented along a common axis of rotation A₁. The disk and spacer pairs 14 may all have similar configurations and, as such, only a single disk and spacer pair 14 will be described.

Each of a disk 16 and a spacer 18 of the disk and spacer pairs 14 may have a respective contacting face 20, 22 defining an engagement between the disk 16 and the spacer 18. That is, at least some portion of the contacting face 20 of the disk 16 and at least some portion of the contacting face 22 of the spacer 18 may interface or connect to define the engagement. As used herein, the contacting faces 20, 22 of the disk 16 and the spacer 18 may include surfaces of the respective components that face one another.

The disk 16 may have a generally cylindrical body, which may or may not be hollow, including or supporting a plurality of static blades. The spacer 18 may have a thin ring-shaped body for providing space, along the common axis of rotation A₁, between the disks 16 and, thus, providing an inner flowpath for working fluid. Each spacer 18 of the disk and spacer pairs 14 may be the same material as the corresponding disk 16, which may, for example, include stainless steel. Although a specific embodiment is described, the present disclosure may be applicable to disks and spacers having various shapes, size, materials, and configurations.

The contacting face 20, 22 of each of the disk 16 and the spacer 18 may include a respective recessed area 24, 26. The recessed areas 24, 26, which may be recessed relative to the respective contacting face 20, 22, may be aligned such that a pin 28 may be positioned as shown. In particular, the recessed areas 24, 26 may be aligned along an axis parallel to the common axis of rotation A₁. The pin 28 may generally include a stem 30 and a head 32 and, as will be discussed below, the stem 30 may be received at least partly within the recessed area 24 of the disk 16 and the head 32 may be received at least partly within the recessed area 26 of the spacer 18. During operation of the turbine engine 10, a thermal interference engagement between the disk 16 and the spacer 18 may secure the engagement of the disk 16, spacer 18, and pin 28.

The exemplary pin 28, including the stem 30 and the head 32, is shown generally in FIGS. 2-5. The head 32 of the pin 28 may include a plurality of flats, or planar surfaces, 40. According to the exemplary embodiment, the head 32 may have a hexagonal shape, including six straight sides and angles. As such, the recessed area 26, or portions thereof, of the spacer 18 may have a shape corresponding to the hexagonal shape of the head 32, or a portion of the head 32, of the pin 28. As shown, the stem 30 of the pin 28 may have a cylindrical shape, with the recessed area 24, or portions thereof, of the disk 16 having a shape corresponding to the cylindrical shape of the stem 30, or a portion of the stem 30, of the pin 28. The pin 28 may be made from a variety of different materials, including, for example, the same material as one or both of the disk 16 and the spacer 18. Further, according to some embodiments, the pin 28 may have a passage 42 therethrough oriented along a longitudinal axis A₂ of the pin 28. The passage 42 may provide an escape of air when the pin 28 is pressed into a blind hole.

As stated above, but referring now to FIGS. 6 and 7, the stem 30 of the pin 28 is shown received within the recessed area 24 of the disk 16, and the head 32 of the pin 28 is shown received within the recessed area 26 of the spacer 18. The stem 30 of the pin 28 may have a substantially cylindrical body, which may be received within a substantially cylindrical opening or cavity of the recessed area 24. Thus, the recessed area 24 may be shaped, sized, and/or configured to receive the stem 30, such as with a frictional fit.

The head 32 of the pin 28, according to the present disclosure, may include at least two flats 40 corresponding to complementary surfaces of the recessed area 26 of the spacer 18. That is, the recessed area 26 may include planar surfaces having similar angles as corresponding surfaces of the head 32 of the pin 28. Thus, the recessed area 26 may be shaped, sized, and/or configured such that at least one of the flats 40 contacts or engages a corresponding surface of the recessed area 26 during operation and/or shutdown of the turbine engine 10.

As shown in FIG. 7, a predetermined clearance 50 may be provided between a top surface 52 of the head 32 of the pin 28 and an inner surface 54 of the recessed area 26 of the spacer 18. As will be discussed below, the predetermined clearance 50 may be reduced, such as during a hot shutdown of the turbine engine 10, as the spacer 18 cools and shrinks more quickly than the corresponding disk 16. The predetermined clearance 50 may be as small as, for example, 0.005 inch; however, the predetermined clearance 50 may vary, depending on the particular application.

The spacer 18 is shown in FIGS. 8, 9 and 10 and may include a thin ring-shaped body. The spacer 18 may be sized, shaped, and/or configured to interact with the corresponding disk 16 in the manner described herein. The spacer 18 may include at least one recessed area 26. As shown more specifically in FIG. 8, the spacer 18 may include a plurality of recessed areas 26, such as, for example, four recessed areas 26, spaced about the spacer 18. According to such an embodiment, the disk 16 may have a corresponding number of recessed areas 24, with a corresponding number of pins 28, such as four pins 28, configured for receipt within the plurality of recessed areas 24, 26.

As stated above, the head 32 of the pin 28 may include a plurality of flats 40. As such, the recessed area 26 of the spacer 18 may have a shape corresponding to the shape of the head 32 of the pin 28. During operation of the turbine engine 10 or during a shutdown, such as a hot shutdown, the spacer 18 may cool more quickly than the corresponding disk 16, thus reducing the predetermined clearance 50 and causing one or more of the flats 40 to engage one or more corresponding surface of the recessed area 26.

INDUSTRIAL APPLICABILITY

The present disclosure relates generally to turbine engines and, more particularly, to an axial compressor of a turbine engine. Further, the present disclosure relates to an axial compressor having a plurality of disk and spacer pairs. Yet further, the present disclosure is applicable to a pin for reducing relative rotational movement of a disk and a spacer of the disk and spacer pairs.

Referring generally to FIGS. 1-11, an exemplary turbine engine 10 includes an axial compressor 12. The axial compressor 12 includes a plurality of disk and spacer pairs 14 oriented along a common axis of rotation A₁. Each of a disk 16 and a spacer 18 of the disk and spacer pairs 14 have a contacting face 20, 22 defining an engagement between the disk 16 and the spacer 18. The contacting face 20, 22 of each of the disk 16 and the spacer 18 includes at least one recessed area 24, 26 for receiving a pin 28. The pin 28 has a stem 30 received within the recessed area 24 of the disk 16, and a head 32, including a plurality of flats 40, received within the recessed area 26 of the spacer 18.

Referring specifically to FIG. 11, a flow diagram 60 representing primary steps of a method of operating the turbine engine 10 or, more particularly, the axial compressor 12, according to the present disclosure, is shown. At a first step, at box 62, the method includes a step of rotating the disk and spacer pair 14 about a common axis of rotation A₁. At some point during rotation of the disk and spacer pair 14, such as during operation and/or shutdown of the turbine engine 10, a contacting face 20 of the disk 16 may engage a contacting face 22 of the spacer 18, at box 64.

During operation of the turbine engine 10, a thermal interference engagement between the disk 16 and the spacer 18 of the disk and spacer pair 14 may form. That is, the disk 16, spacer 18, and pin 28 may be configured to rotate together using a frictional fit or engagement. During a hot shutdown, or other similar condition, of the turbine engine 10, a predetermined clearance 50 between a top surface 52 of the head 32 of the pin 28, and an inner surface 54 of the recessed area 26 of the spacer 18 may be reduced.

During the operation and/or shutdown, relative rotation of the disk 16 and the spacer 18 may be reduced or restricted using the pin 28, which has the stem 30 received within the recessed area 24 of the disk 16, and the head 32 received within the recessed area 26 of the spacer 18, at box 66. The restricting step includes contacting at least two flats 40 of the head 32 of the pin 28 with complementary surfaces of the recessed area 26 of the spacer 18, at box 68. According to some embodiments, the restricting step may include engaging four pins 28 with four recessed areas 24, 26 spaced about each of the disk 16 and the spacer 18.

Some conventional axial compressors utilize small cylindrical pins having an interference fit with one or both of a disk and spacer. During a hot shutdown of the turbine engine, the spacer may cool and shrink at a higher rate than the corresponding disk. This may relieve the designed interference fit and cause the spacer to become loose on the disk. The small cylindrical pin is often insufficient to restrain the spacer in the circumferential direction. The force exerted on the pin by the rotational inertia of the spacer may cause the pin to break, thereby freeing the spacer to rotate relative to the disk from the factory setting.

The pin of the present disclosure, as described herein, reduces clocking and provides a more durable and robust engagement of the disk and spacer in the context of an axial compressor, or other similar context. In particular, for example, and during a hot shutdown, of the turbine engine, the spacer may cool more quickly than the corresponding disk, thus reducing the predetermined clearance and causing one or more of the flats to engage one or more corresponding surface of the recessed area.

It should be understood that the above description is intended for illustrative purposes only, and is not intended to limit the scope of the present disclosure in any way. Thus, those skilled in the art will appreciate that other aspects of the disclosure can be obtained from a study of the drawings, the disclosure and the appended claims. 

What is claimed is:
 1. An axial compressor of a turbine engine, including: a plurality of disk and spacer pairs oriented along a common axis of rotation, each of a disk and a spacer of the disk and spacer pairs having a contacting face defining an engagement between the disk and the spacer; the contacting face of each of the disk and the spacer including a recessed area; and a pin having a stem received within the recessed area of the disk and a head received within the recessed area of the spacer; the head of the pin including at least two flats corresponding to complementary surfaces of the recessed area of the spacer.
 2. The axial compressor of claim 1, wherein the disk and the spacer have a thermal interference engagement.
 3. The axial compressor of claim 1, wherein the head of the pin has a hexagonal shape.
 4. The axial compressor of claim 3, wherein the recessed area of the spacer has a shape corresponding to the hexagonal shape of the head of the pin.
 5. The axial compressor of claim 3, wherein the stem of the pin has a cylindrical shape.
 6. The axial compressor of claim 5, wherein the recessed area of the disk has a shape corresponding to the cylindrical shape of the stem of the pin.
 7. The axial compressor of claim 3, wherein the pin has a passage therethrough oriented along a longitudinal axis of the pin.
 8. The axial compressor of claim 1, further including a plurality of recessed areas spaced about each of the disk and the spacer, and four pins configured for receipt within the plurality of recessed areas.
 9. The axial compressor of claim 1, further including a predetermined clearance between a top surface of the head of the pin and an inner surface of the recessed area of the spacer.
 10. A method of operating a turbine engine, including steps of: rotating a disk and spacer pair of a plurality of disk and spacer pairs about a common axis of rotation; engaging a contacting face of a disk of the disk and spacer pairs with a contacting face of a spacer of the disk and spacer pairs during rotation; and restricting relative rotation of the disk and the spacer using a pin having a stem received within a recessed area of the disk and a head received within a recessed area of the spacer; wherein the restricting step includes contacting at least two flats of the head of the pin with complementary surfaces of the recessed area of the spacer.
 11. The method of claim 10, further including forming a thermal interference engagement of the disk and the spacer during operation of the turbine engine.
 12. The method of claim 11, further including performing a hot shutdown of the turbine engine, and reducing a predetermined clearance between a top surface of the head of the pin and an inner surface of the recessed area of the spacer.
 13. The method of claim 10, further including engaging a hexagonally shaped head of the pin with the complementary surfaces of the recessed area of the spacer.
 14. The method of claim 10, wherein the restricting step includes engaging four pins with four recessed areas spaced about each of the disk and the spacer.
 15. A turbine engine, including: an axial compressor, including: a plurality of disk and spacer pairs oriented along a common axis of rotation, each of a disk of the disk and spacer pairs and a spacer of the disk and spacer pairs having a contacting face defining an engagement between the disk and the spacer, the contacting face of each of the disk and the spacer including a recessed area; and a pin having a stem received within the recessed area of the disk and a hexagonally shaped head received within the recessed area of the spacer.
 16. The turbine engine of claim 15, wherein the pin has a passage therethrough oriented along a longitudinal axis of the pin.
 17. The turbine engine of claim 15, wherein the stem of the pin has a cylindrical shape.
 18. The turbine engine of claim 15, wherein the disk and the spacer have a thermal interference engagement.
 19. The turbine engine of claim 15, further including a predetermined clearance between a top surface of the head of the pin and an inner surface of the recessed area of the spacer.
 20. The turbine engine of claim 15, further including a plurality of recessed areas spaced about each of the disk and the spacer, and four pins configured for receipt within the plurality of recessed areas. 